A conventional process of manufacturing semiconductor substrates (hereinafter, simply referred to as “substrates”) involves performing various types of processing on the substrates. For example, chemical-solution processing such as etching is performed on a surface of a substrate that has a resist pattern on the surface by supplying a chemical solution onto the substrate. After completion of the chemical-solution processing, cleaning processing is performed by supplying a cleaning liquid onto the substrate, and then dry processing is performed on the substrate.
In a substrate processing apparatus disclosed in Japanese Patent Application Laid-Open No. H11-176795 (Document 1), an interrupt member is disposed in close proximity to the upper surface of a substrate to form a space between the interrupt member and the substrate when a series of processes including chemical-solution processing, cleaning processing, and dry processing are to be performed on the substrate. Then, a chemical solution and a cleaning liquid are sequentially supplied to that space, and thereafter the substrate is rotated at a high speed to complete the above series of processes. In the substrate processing apparatus, a nitrogen gas is supplied to the space between the interrupt member and the substrate, and thus the above series of processes are performed in a hypoxic atmosphere.
Similarly, in a substrate processing apparatus disclosed in Japanese Patent Application Laid-Open No. 2004-158482 (Document 2), a series of processes including chemical-solution processing, cleaning processing, and dry processing are performed on a substrate in a state where an atmosphere shielding plate is in close proximity to the upper surface of the substrate. The substrate processing apparatus starts the supply of a nitrogen gas to the space between the atmosphere shielding plate and the substrate after the cleaning processing has proceeded to some extent. In parallel with the supply of the nitrogen gas, the atmosphere shielding plate is moved to a position closer to the substrate, and at this position the cleaning processing is continued and the dry processing is performed. This enables the amount of nitrogen gas supplied to be reduced.
Since the aforementioned interrupt member is in close proximity to the substrate, the chemical solution or the cleaning liquid may adhere to the lower surface of the interrupt member and drop onto the dried substrate. The chemical solution adhering to the lower surface of the interrupt member may also dry and adhere to the substrate as particles. In addition, a chemical atmosphere (i.e., an atmosphere containing mist and fumes of a chemical solution) produced in the space between the interrupt member and the substrate is exhausted during the chemical-solution processing through an exhaust port or the like at the bottom of a cup part disposed around the substrate. However, it is difficult to efficiently suck out the chemical atmosphere from around the substrate because of the small distance between the interrupt member and the substrate.
On the other hand, if the interrupt member and the substrate are widely separated from each other during the chemical-solution processing, the amount of the chemical atmosphere that remains in the space between the interrupt member and the substrate will increase. The chemical atmosphere will be reduced to some extent during the cleaning processing by being exhausted through the aforementioned exhaust port, but still remains after the cleaning processing and may possibly cause particles during the dry processing. If the chemical atmosphere is to be removed completely during the cleaning processing, the amount of time required for the cleaning processing will increase and production efficiency will decrease.